| Records |
| Author |
Mandal, R.; Murgui, C.; Peñuelas, A.; Pich, A. |
| Title |
The role of right-handed neutrinos in b -> c tau nubar anomalies |
Type |
Journal Article |
| Year |
2020 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume  |
08 |
Issue |
8 |
Pages |
022 - 46pp |
| Keywords |
Phenomenology of Field Theories in Higher Dimensions |
| Abstract |
Motivated by the persistent anomalies reported in the b -> c tau v<overbar></mml:mover> data, we perform a general model-independent analysis of these transitions, in the presence of light right-handed neutrinos. We adopt an effective field theory approach and write a low-energy effective Hamiltonian, including all possible dimension-six operators. The corresponding Wilson coefficients are determined through a numerical fit to all available experimental data. In order to work with a manageable set of free parameters, we define eleven well- motivated scenarios, characterized by the different types of new physics that could mediate these transitions, and analyse which options seem to be preferred by the current measurements. The data exhibit a clear preference for new-physics contributions, and good fits to the data are obtained in several cases. However, the current measurement of the longitudinal D<SUP></SUP> polarization in B -> D tau v<overbar></mml:mover> cannot be easily accommodated within its experimental 1 sigma range. A general analysis of the three-body B -> D tau v<overbar></mml:mover> and four-body B -> D<mml:mo><mml:mfenced close=“)” open=“(”><mml:mo>-> D pi</mml:mfenced>tau <mml:mover accent=“true”>v<mml:mo stretchy=“true”><overbar></mml:mover> angular distributions is also presented. The accessible angular observables are studied in order to assess their sensitivity to the different new physics scenarios. Experimental information on these distributions would help to disentangle the dynamical origin of the current anomalies. |
| Address |
[Mandal, Rusa] Univ Siegen, Theoret Phys 1, Nat Wissensch Tech Fak, D-57068 Siegen, Germany, Email: Rusa.Mandal@uni-siegen.de; |
| Corporate Author |
|
Thesis |
|
| Publisher |
Springer |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1029-8479 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000561056000003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4506 |
| Permanent link to this record |
| |
|
| |
| Author |
Durieux, G.; Irles, A.; Miralles, V.; Peñuelas, A.; Perello, M.; Poschl, R.; Vos, M. |
| Title |
The electro-weak couplings of the top and bottom quarks – Global fit and future prospects |
Type |
Journal Article |
| Year |
2019 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
12 |
Issue |
12 |
Pages |
098 - 44pp |
| Keywords |
Phenomenology of Field Theories in Higher Dimensions |
| Abstract |
We evaluate the implications of LHC and LEP/SLC measurements for the electro-weak couplings of the top and bottom quarks. We derive global bounds on the Wilson coefficients of ten two-fermion operators in an effective field theory description. The combination of hadron collider data with Z -pole measurements is found to yield tight limits on the operator coefficients that modify the left-handed couplings of the bottom and top quark to the Z boson. We also present projections for the high-luminosity phase of the LHC and for future electron-positron colliders. The bounds on the operator coefficients are expected to improve substantially during the remaining LHC programme, by factors of 1 to 5 if systematic uncertainties are scaled as statistical ones. The operation of an e(+)e(-) collider at a center-of-mass energy above the top-quark pair production threshold is expected to further improve the bounds by one to two orders of magnitude. The combination of measurements in pp and e(+)e(-) collisions allows for a percent-level determination of the top-quark Yukawa coupling, that is robust in a global fit. |
| Address |
[Durieux, Gauthier] Technion Israel Inst Technol, Dept Phys, IL-3200003 Haifa, Israel, Email: durieux@campus.technion.ac.il; |
| Corporate Author |
|
Thesis |
|
| Publisher |
Springer |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1029-8479 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000513489700002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4280 |
| Permanent link to this record |
